Usecases for NoSQL Databases

[1]
https://www.mongodb.com/products/compass

Love these marketing slides, UI

[2]
No SQL databases has its own technical jargon
- Good choice for graph data-structutes
- Geo-spatial problem solving 

https://www.thoughtworks.com/insights/blog/nosql-databases-overview

[3]

From Business Perspective, What to Choose When 
Its a Battle
https://www.analyticsindiamag.com/nosql-vs-sql-database-type-better-big-data-applications/

Comparsion
https://blog.knoldus.com/mongodb-vs-rdbms-and-its-adavanatges/

 ..

MongoDB emphasizes on CAP theorem (Consistency, Availability, and Partition tolerance) but RDBMS emphasizes on ACID properties (Atomicity, Consistency, Isolation and Durability).

There is no support for complex joins in MongoDB but RDBMS supports complex joins which can be difficult to understand and take too much time to execute.

In MongoDB, Conversion/mapping of application objects to database objects is not needed.

..
[4] 

Maintaining Schema in a Distributed System

MemSQL implements schema by storing the metadata in small internal database and synchronously replicating the metadata to all the nodes when it is changed. It uses a two-phase commit to ensure that DDL changes propagate properly through the cluster and are built in a way so that they do not block select queries.
MemSQL supports more than just relational though. You can type a column as JSON and store a JSON document in it. If you decide there are some columns you want to query later, you can project the properties as columns and index them. MemSQL also supports Spatial types and Full-Text indexes as well. We understand that customers need a mix of data types in a system that is familiar and where all the types of data can co-exist naturally.

https://www.memsql.com/blog/why-nosql-databases-wrong-tool-for-modern-application/

Google Search
Keyword 
mongoDB vs RDBMS
and follow People Usually ask

:) 

[5]

Big Question ? Is JSON structure better than LDIF format for LDAP entry/ searches ??

https://ldap3.readthedocs.io/tutorial_searches.html

Why this question all of sudden.
- we are in 2020
- there is python thats getting more popular
- compact scripting need of hour
- results should not be maggled in special characters and unneccsary tags <> {} [ ] :

- we thought we can make life by processing DB ( RDBMS table)  change notification in 2016 but LDAP entry change notification processing , definition of rules will be needs in 2020

- Moral : known your data formats and there constraints in same way you know your programming languages their pro's and Cons

All the best
:)